From patchwork Sat Jun 18 00:20:43 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Philippe Blain via GitGitGadget X-Patchwork-Id: 12886157 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 89B53C43334 for ; Sat, 18 Jun 2022 00:21:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1383624AbiFRAVI (ORCPT ); Fri, 17 Jun 2022 20:21:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383234AbiFRAVH (ORCPT ); Fri, 17 Jun 2022 20:21:07 -0400 Received: from mail-wr1-x431.google.com (mail-wr1-x431.google.com [IPv6:2a00:1450:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B934559308 for ; Fri, 17 Jun 2022 17:21:03 -0700 (PDT) Received: by mail-wr1-x431.google.com with SMTP id g27so864459wrb.10 for ; Fri, 17 Jun 2022 17:21:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:in-reply-to:references:from:date:subject:fcc :content-transfer-encoding:mime-version:to:cc; bh=BKlm205JGRDRHfyY2bKLwJl/MLPPButVvrByw19Bmm0=; b=EN4x4X2TqT1tA6DTR2aX8DDgsMLQ2K2q3EEalhhZN0PK+mfnUrIw+KBC6f8126We2W aq617JCi9ew0vjwBURkw7jzo4Xh8+T62xxfWZ9B5UhR7EDJDXnjwMl8G/iqDKkofU0rT xy82fKfqgEQGpa38B+15jm+zwe/dYMIAsADbSHpn29iUfmV45QiqBuswomQ0UTTm43Xc NkuHa7fZQ9BXTKSBYe6mmwwobHLP07PJYc2YpYlM/IhET6rWiSQBKwz9xYN+ZcNSlzOY 3yqqrknjd1WDAyoTISKoY7MXjjIWKmjC2l0JzgEdqp8IJVZEIWyv3bzIKqhvKNLZbd/e oSOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:in-reply-to:references:from:date :subject:fcc:content-transfer-encoding:mime-version:to:cc; bh=BKlm205JGRDRHfyY2bKLwJl/MLPPButVvrByw19Bmm0=; b=K8utmE2FPMhPUVkBmviPYMHuhsuMutf1foBeAGFht4ysFUAkiKT9qsoWjxP4Mq2iR+ IHUatd6Q3rpcNq9N1f3019nP2S+YGr0TeGioB+/AY0kiEbV2A2i0DLJwXW3P0wxtiulK 7Woefr3De+DqnOFZQGEX728rboJvnpY1f2Q4zCy9BILnyU7juOVhK4ztfXz/CdkKmQXe pz9TaXslwH/OUwiVuxTQNq0VJbXR4m3FSYzOZfqHE+WVXUUDpHUvZB/RJA4EspqZ6aDY 7U+LeH0MRFbpRFlBW+oQc0tFAqhdiWLo1TfxKVxKvX8taLuAdpln5TP3bSrXjDB7GFeg evwQ== X-Gm-Message-State: AJIora8IlGNLAmfYetKWGGL0Ljsn0Gy+iMMJdSLn9NkUy5Zj9VzHiSBt h5ARn1kD33wIrIQGK+RzOyx6DStEh4+fTA== X-Google-Smtp-Source: AGRyM1uVWtnSeEOKsCzYn56tFD92k61FBA8DBH6O5dA92wm0oJSqwvxfo8MYcazAOBmf/RRLdBG7Gw== X-Received: by 2002:a05:6000:1869:b0:211:7f25:89da with SMTP id d9-20020a056000186900b002117f2589damr11790273wri.696.1655511661742; Fri, 17 Jun 2022 17:21:01 -0700 (PDT) Received: from [127.0.0.1] ([13.74.141.28]) by smtp.gmail.com with ESMTPSA id cc3-20020a5d5c03000000b00213ba3384aesm5383887wrb.35.2022.06.17.17.21.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jun 2022 17:21:01 -0700 (PDT) Message-Id: In-Reply-To: References: From: "Elijah Newren via GitGitGadget" Date: Sat, 18 Jun 2022 00:20:43 +0000 Subject: [PATCH v7 00/17] In-core git merge-tree ("Server side merges") Fcc: Sent MIME-Version: 1.0 To: git@vger.kernel.org Cc: Christian Couder , Taylor Blau , Johannes Altmanninger , Ramsay Jones , Johannes Schindelin , Christian Couder , =?utf-8?b?UmVuw6k=?= Scharfe , =?utf-8?b?w4Z2YXIgQXJuZmrDtnI=?= =?utf-8?b?w7A=?= Bjarmason , Elijah Newren , Johannes Sixt , Josh Steadmon , Emily Shaffer , Elijah Newren Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Sorry for the long delay. Much thanks to Johannes for tying up the loose ends and making several improvements seen in this round. Note: rebased on main (it's been 4 months since v6, and there were a few conflicts...). == Basic Summary == This series introduces a new mode to git merge-tree allowing it to perform real merges (three-way text content merges, recursive ancestor consolidation, rename detection, proper directory/file conflict handling, etc.) and write the result as a toplevel tree. It doesn't touch the working tree or index, and doesn't create any commits or update any refs. It could be used to do merges when in a bare repository (thus potentially making it of interest to Git hosting sites, i.e. "Server side merges"), or for doing a merge of branches that aren't checked out. It does not handle similar functionality for cherry-picks, rebases, or reverts; that is also of interest, but is being deferred for a future series. == Quick Overview == * Patches 1-2: preparatory cleanups * Patches 3-4: implement basic real merges * Patches 5-6: include informational messages ("CONFLICT" messages and such) in output * Patches 7-15: add ability to include ls-files -u style of info in the output * Patch 16: support --allow-unrelated-histories * Patch 17: augment the manual with potential usage mistakes == Updates Log == Stuff NOT included that reviewers brought up in various rounds (and which might still be an open question): * Very generic (mode, oid, stage, filename) printing formatting[3] * Providing similar functionality for doing cherry-picks/rebases/reverts, i.e. a scheme for three-way merges with a specified merge-base[4]. That's being deferred to a future series. [3] https://lore.kernel.org/git/CABPp-BGnOes7J_piDyBUeuLVm274w4-9G3k0vR-0it3z7TPn_w@mail.gmail.com/ [4] https://lore.kernel.org/git/CABPp-BEaemkGGm0cSofP0gau7YN-y6HFoi0yJbHA8+iGjxsYSA@mail.gmail.com/ Updates since v6: * Significant merge-ort changes to support machine-parseable information about individual conflicts and the paths involved in each, rather than just a group of free-form output messages that may change over time. This includes 5 new patches, 2 written by Johannes (and with breaking out the other 3 from some work-in-progress changes I had including some fixes and improvements he added). Updates since v5: * Used reverse_commit_list() to reverse a commit_list without extra allocations * Several documentation updates Updates since v4: * Fixed double "is" in documentation. * Fixed a few small items with testcases Updates since v3: * Dropped previous patches 5, 6, and 8 of the old series; they weren't being used and opened a can of worms[1] * [Patch 3] Restructured argument checking, including using an enum * [Patch 4] Restored the extended paragraph about the deprecated form of git-merge-tree, mentioned write-tree in plumbing commands, and a few other small fixups to the documentation * [Patch 4] Also provide an example of a clean merge rather than just a conflicted one * [Patch 6] Fix the incompatible arguments check and add some tests for it * [Patch 6] Introduce an anonymize_hash() shell function to make tests easier to read (less repeated sed) * [Patch 9] Rename --exclude-modes-oids-stages to --name-only; no short option for now * [Patch 10] When -z passed, the tree in the first section should have a trailing NUL rather than trailing newline [1] https://lore.kernel.org/git/CABPp-BEKuXHELVx4=5JJTj5HVOKZ=Y-4G4BK47BCZYYRSrkFsQ@mail.gmail.com/ Updates since v2: * Improved patches from Dscho for the diff_warn_rename_limit() handling * Add a -z option for NUL-terminated conflict info lines (so that filenames do not have to be quoted) Updates since v1 (or v3 depending on how you count; thanks to René, Ævar, Christian, Dscho for very helpful feedback): * New patch from Dscho allowing diff_warn_rename_limit() to print somewhere other than stdout (I hope he's okay with me including his Signed-off-by) * Now prints filenames relative to prefix, much like ls-files * Renamed --exclude-oids-and-modes to --exclude-modes-oids-stages and gave it a -l shorthand; I'm wondering if I should just drop this option, though. * And numerous cleanups, in lots of areas: * Multiple parse-options cleanups * Lots of commit message cleanups * Wording tweaks to the "Description" section of the manual * Several small code cleanups * I dropped the RFC label [There were also two submissions of a previous series; see https://lore.kernel.org/git/pull.1114.v2.git.git.1641403655.gitgitgadget@gmail.com/] [https://lore.kernel.org/git/pull.1114.v2.git.git.1641403655.gitgitgadget@gmail.com/%5D] Updates since original submission v2 (thanks to Christian, Dscho, Ramsay, and René for suggestions and comments): * Significant changes to output format: * Flags no longer take a filename for additional output; they write to stdout instead. * More information included by default when there are conflicts (no need to request it with additional flags, instead flags can be used to suppress it). * Provide (mode, oid, stage, file) tuples -- i.e. ls-files -u style of information -- when there are conflicts. Add a flag to only list conflicted files if that's preferred. * Much more thorough manual for git-merge-tree.txt * Renamed option from --real to --write-tree * Accept an optional --trivial-merge option to get old style merge-tree behavior * Allow both --write-tree and --trivial-merge to be omitted since we can deduce which from number of arguments * Document exit code when the merge cannot be run (so we can distinguish other error cases from conflicts) * testcase cleanups: test_tick, early skip of test when using recursive backend, variable renames, etc. * various minor code cleanups * Add a new --allow-unrelated-histories option (with same meaning as the one used in git merge) * Rebased on top of en/remerge-diff to avoid a small conflict Updates since original submission v1 (thanks to Johannes Altmanninger and Fabian for suggestions): * Fixed a bad patch splitting, and a style issue pointed out by Johannes Altimanninger * Fixed misleading commit messages in new test cases * Fixed my comments about how commit-tree could be used to correctly use two -p flags Elijah Newren (15): merge-tree: rename merge_trees() to trivial_merge_trees() merge-tree: move logic for existing merge into new function merge-tree: add option parsing and initial shell for real merge function merge-tree: implement real merges merge-ort: split out a separate display_update_messages() function merge-tree: support including merge messages in output merge-ort: provide a merge_get_conflicted_files() helper function merge-ort: remove command-line-centric submodule message from merge-ort merge-tree: provide a list of which files have conflicts merge-tree: provide easy access to `ls-files -u` style info merge-ort: store more specific conflict information merge-ort: optionally produce machine-readable output merge-tree: allow `ls-files -u` style info to be NUL terminated merge-tree: add a --allow-unrelated-histories flag git-merge-tree.txt: add a section on potentional usage mistakes Johannes Schindelin (2): merge-ort: store messages in a list, not in a single strbuf merge-ort: make `path_messages` a strmap to a string_list Documentation/git-merge-tree.txt | 235 ++++++++++++++- builtin/merge-tree.c | 187 +++++++++++- diff.c | 27 +- git.c | 2 +- merge-ort.c | 474 ++++++++++++++++++++++--------- merge-ort.h | 32 ++- t/t4301-merge-tree-write-tree.sh | 240 ++++++++++++++++ t/t6437-submodule-merge.sh | 2 +- 8 files changed, 1032 insertions(+), 167 deletions(-) create mode 100755 t/t4301-merge-tree-write-tree.sh base-commit: ab336e8f1c8009c8b1aab8deb592148e69217085 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1122%2Fnewren%2Fin-core-merge-tree-v7 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1122/newren/in-core-merge-tree-v7 Pull-Request: https://github.com/gitgitgadget/git/pull/1122 Range-diff vs v6: 1: 4a7cd5542bb = 1: 8fb51817ed4 merge-tree: rename merge_trees() to trivial_merge_trees() 2: 4780ff6784d = 2: 8e0a79fa1ad merge-tree: move logic for existing merge into new function 3: 60253745f5c = 3: baf0950bcb6 merge-tree: add option parsing and initial shell for real merge function 4: f8266d39c1b = 4: 697470e50ae merge-tree: implement real merges 5: 6629af14919 = 5: 069af1ecc30 merge-ort: split out a separate display_update_messages() function 6: 17b57efb714 = 6: 53c92a5d8d9 merge-tree: support including merge messages in output 7: 4c8f42372dd = 7: 67a728d35f0 merge-ort: provide a merge_get_conflicted_files() helper function -: ----------- > 8: 6419487e26b merge-ort: remove command-line-centric submodule message from merge-ort 8: 7b1ee417f3d ! 9: c92b81e7366 merge-tree: provide a list of which files have conflicts @@ builtin/merge-tree.c: static int real_merge(struct merge_tree_options *o, + string_list_clear(&conflicted_files, 1); + } if (o->show_messages) { - printf("\n"); +- printf("\n"); ++ putchar(line_termination); merge_display_update_messages(&opt, &result); + } + merge_finalize(&opt, &result); @@ builtin/merge-tree.c: int cmd_merge_tree(int argc, const char **argv, const char *prefix) /* Do the relevant type of merge */ 9: f1231a8fbc8 = 10: d7360f58f16 merge-tree: provide easy access to `ls-files -u` style info -: ----------- > 11: f523b08ab5a merge-ort: store messages in a list, not in a single strbuf -: ----------- > 12: 6b47c0fdbd7 merge-ort: make `path_messages` a strmap to a string_list -: ----------- > 13: 7eb70f77c81 merge-ort: store more specific conflict information -: ----------- > 14: 662e97f2ed4 merge-ort: optionally produce machine-readable output 10: 22297e6ce75 ! 15: b314aa9c436 merge-tree: allow `ls-files -u` style info to be NUL terminated @@ builtin/merge-tree.c: static int real_merge(struct merge_tree_options *o, if (!result.clean) { struct string_list conflicted_files = STRING_LIST_INIT_NODUP; const char *last = NULL; -@@ builtin/merge-tree.c: static int real_merge(struct merge_tree_options *o, - string_list_clear(&conflicted_files, 1); - } - if (o->show_messages) { -- printf("\n"); -+ putchar(line_termination); - merge_display_update_messages(&opt, &result); - } - merge_finalize(&opt, &result); @@ builtin/merge-tree.c: int cmd_merge_tree(int argc, const char **argv, const char *prefix) N_("do a trivial merge only"), MODE_TRIVIAL), OPT_BOOL(0, "messages", &o.show_messages, @@ t/t4301-merge-tree-write-tree.sh: test_expect_success 'Check conflicted oids and + + test_expect_code 1 git merge-tree --write-tree -z tweak1 side2 >out && + anonymize_hash out >actual && ++ printf "\\n" >>actual && + + # Expected results: + # "greeting" should merge with conflicts @@ t/t4301-merge-tree-write-tree.sh: test_expect_success 'Check conflicted oids and + + EOF + -+ cat <<-EOF >>expect && -+ Auto-merging greeting -+ CONFLICT (content): Merge conflict in greeting -+ CONFLICT (file/directory): directory in the way of whatever from tweak1; moving it to whatever~tweak1 instead. -+ CONFLICT (modify/delete): whatever~tweak1 deleted in side2 and modified in tweak1. Version tweak1 of whatever~tweak1 left in tree. -+ Auto-merging Αυτά μου φαίνονται κινέζικα -+ CONFLICT (content): Merge conflict in Αυτά μου φαίνονται κινέζικα ++ q_to_nul <<-EOF >>expect && ++ 1QgreetingQAuto-mergingQAuto-merging greeting ++ Q1QgreetingQCONFLICT (contents)QCONFLICT (content): Merge conflict in greeting ++ Q2Qwhatever~tweak1QwhateverQCONFLICT (file/directory)QCONFLICT (file/directory): directory in the way of whatever from tweak1; moving it to whatever~tweak1 instead. ++ Q1Qwhatever~tweak1QCONFLICT (modify/delete)QCONFLICT (modify/delete): whatever~tweak1 deleted in side2 and modified in tweak1. Version tweak1 of whatever~tweak1 left in tree. ++ Q1QΑυτά μου φαίνονται κινέζικαQAuto-mergingQAuto-merging Αυτά μου φαίνονται κινέζικα ++ Q1QΑυτά μου φαίνονται κινέζικαQCONFLICT (contents)QCONFLICT (content): Merge conflict in Αυτά μου φαίνονται κινέζικα ++ Q + EOF + + test_cmp expect actual 11: db73c6dd823 = 16: 66df0c2e837 merge-tree: add a --allow-unrelated-histories flag 12: d58a7c7a9f6 ! 17: 70ea8281952 git-merge-tree.txt: add a section on potentional usage mistakes @@ Documentation/git-merge-tree.txt: with linkgit:git-merge[1]: +<> section has the necessary info, though it +is not designed to be machine parseable. + ++Do NOT assume that each paths from <>, and ++the logical conflicts in the <> have a ++one-to-one mapping, nor that there is a one-to-many mapping, nor a ++many-to-one mapping. Many-to-many mappings exist, meaning that each ++path can have many logical conflict types in a single merge, and each ++logical conflict type can affect many paths. ++ +Do NOT assume all filenames listed in the <> +section had conflicts. Messages can be included for files that have no +conflicts, such as "Auto-merging ".